Bootiful Spring Boot 3.x by Josh Long

Java 21 is considered the most technologically important Java release, offering significant improvements in performance, syntax features like virtual threads, records, sealed types and pattern matching

Spring Boot 3.x requires Java 17 minimum, but Java 21+ is recommended for best performance and newer language features

Virtual threads in Java 21 significantly improve application scalability and throughput by allowing more efficient handling of blocking operations

Spring AI provides easy integration with various AI models (OpenAI, Ollama, Hugging Face) and supports RAG (Retrieval Augmented Generation) patterns for building AI-powered applications

Spring Modulith helps build modular monoliths by enforcing architectural boundaries, validating module dependencies, and providing event-driven communication between modules

Event-driven patterns like event notification, event-carried state transfer, and event sourcing help build decoupled, scalable systems

Package-private visibility should be preferred over public to maintain modularity and reduce coupling between components

Spring Data JDBC combined with vector databases (like PG Vector) enables efficient similarity searches and AI/ML integrations

GraalVM native image compilation produces more efficient executables but requires handling reflection and other dynamic features

Modern Spring applications should embrace modular design, event-driven architectures, and newer Java features while limiting public APIs